Hydraulic jack



' and State of Michigan,

' 50 8t base 3 in such a manner as t0 i lPetentedl May 115, 31923...

ARTHUR PAOLI, 0F HANCOCK, MICHIGAN.

HYDRAULIC JACK.

To allwhomz't may con/mm: Be it known that I, ARTHUR PAOLI, a

citizen of the United States, and a resident of Hancock, in the county of Houghton have invented a new and useful Improvement in Hydraulic Jacks, of which the ollowing is a full,

clear, and exact description.

y invention relates to hydraulic jacks, and it consists in the combinations, constructions and arrangements herein described and claimed.

An object of my invention is to provide a hydraulic jack that is relatively simple' in construction and operation and is therefore capable of being operated readily.

A further object of my invention is. to

provide a device having a liquid-holding receptacle and means. for returning the power' liquid to the receptacle when the work-engaging member of the device has been raised to a predetermined height, whereby the work engaging member of the device cannot be moved out of operative position when the operation of the device is continued. y A further object of my invention is to provide a device of the character described having means for permitting the escape of air from the liquid used in the device with- 1 out permitting any of the fluid to pass therefrom.

Other objects and advantages will appear in the following specification, and the- $5 novel features of the invention ill heparticularly pointed out in the appended claims.

y invention is illustrated in the accompanying drawings, forming part of this application, in which-- Figure 1 is a vertical central section through the device, portions being shown in' elevation, A

gigure 2 is a top plan view of the same, an as Figure 3 is an elevation of auxiliary work supporting elements embodied in the device.

In carrying out my invention, I provide acas'ing 1 that is firmly secured at its lower end by bolts 2, or like fastening means, to rovide a liquid-tight connection between t e casing Application filed May 31, 1921. Serial No. 473,764.

and the base. The casing 1, together with the base, constitutes a receptacle adapted to hold a liquid that is placed therein through a filler opening 4 in the bottom of the base 3.- The filler opening 4 is normally closed by a plug 5 and the casing 1 is inverted when the liquid is introduced thereinto.

A portion of the base 3-protrudes within the c-asin 1. A vertical cylinder 6 is ar- @0 ranged with its lower end disposed within the casing l and closed by an integral cylindrical boss 7 that extends upwardly from v the base 3. The cylinder 6 has a threaded connection at 8 with the walls of'the open- 6 ing in the casing throu 'h which it is projected into the latter, w ereby the cylinder 6 can be adjusted to clamp the lower end thereof against the upper wall of thebase to eflect a liquid-tight connection. A packing gland 9 is provided to prevent leakage of the liquid from the receptacle at the point of connection of the cylinder 6 with the, wall of the opening at 8. The cylinder 6 has a ram or plunger 10 arranged therein '55 and provided with a packing member 11 the inner wal of the cylinder 6. A pump cylinderor casing12'is projected into the casing 1 through an opening 13 and arranged with its lower end disposed within a socket 1 1 in the base 3. A packing gland 15 is provided at the junction of the pump casing 12 and the casing 1. A pump plunea ger 16 arranged for reciprocation in the pump cylinder 12 is connected at its upper end, as by means of a pivot pin 17, to a lever 18. The latter is pivoted at 19 to a link 20 that is in turn pivoted at 21 to a. cclug 22. The latter is integral with the eas- A transverse bore 23 in the base 1 communicates with the pump cylinder 12at its lower end and leads to an inlet passage 24: ea

in the base that is enlarged at 25 to proof the exhaust passage 30 can be operated by means of a stem 32 to prevent or permit the flow of liquid from the cylinder 6 into the receptacle. The stem 32 has a threaded connection at 33 with the wall of the casing and extends exteriorly thereof, being bent laterally adjacent to its upper end to provide a handle 34 for convenience in manipulating the valve stem 31.

From the foregoing description of the 'various parts of the. device, the operation thereof may be readily understood. The lever 18 maybe adapted for connection with -a detachable handle and is operated to reciprocate the pump plunger 16. When the 2 latter is moved upwardly in the pum passages 23, 24, 27 and 29 and the ball valve 28 will be moved from its seat, thereby'permitting a flow of liquid from the receptacle 0 into the pump casing. At the down-stroke of the pump plunger 16, the liquid drawn into the pump cylinder and filling passages 23 and'24 will be forced into the cylinder 6, thereby forcing the ram 10 upwardly and raising work that rests upon a work-engaging member 36 carried at the upper end of i the ram. It isto be observed that the ball valve 28 will be moved from its seat when the pump plunger 16 is moved upwardly and that the ball member 26 will be moved from its seat when the pump plunger is moved downwardly. When the work engaged has been raised to the height desired I or it is desired to' occasion the retraction of the ram 10 for any other-reason, the handle 34 is moved to open the valve 31 and to thereby'permit the return of the liquid from the working cylinder 6to the receptacle. A by-pass conduit 36' communicates with 5 the working cylinder 6 at a spaced distance from the .upper end thereof and-leads to 7 the receptacle 1. A longitudina' ll extending groove 37 in the outer wall 0 the ram 10 extends from the upperor outer end of 5 5 the latter to a spaced distance from the lower end thereof.- The ram 10 is guided in reciprocation b a.' pin 38 protruding a longitudinally extending guideslot 39 in 6 .the ram 10 so that the. groove 37 is in regis try with the opening 0 the by-pass conduit 36 into the cylinder 6. Consequently, when the ram has been raised to the upper end of the bypass 36' in the manner described, k. l i a casing 12, apartial vacuum is created in the" foot 45 relative (to the cylinder. r I

The device comprises relatively few parts rom the inner wal of the cylinder 10 into a ,means for permitting the escape of air from the receptacle without permittin the passage ofthe operating fluid there rom. It will be understood that considerable air is forced into the cylinder 6 together with the operating fluid and that this air is compressed. When the liquid passesv from the cylinder 6 to the receptacle again, the air passes upwardly through the by-pass conduit 36 and along the air groove 37 from the cylinder 6 at the. upper end of the latter. A packing gland 40 may be provided at the upper'end of the cylinder 6 to prevent the leakage of the liquid from the latter.

' The work-engaging member 36 is conventional in form and has oppositely. extending cars 41 and 42. An. auxiliary worksupporting arm 43 is curved adjacent to its upper end to rest upon the work supporting member 36 when the ear 41 is disposed in a slot 44 in the arm 43. -A foot 45 has a-body portion 46 provided with a bore 47 adapted I the latto the arm 43 and is slidable along positlon ter. It may be secured in adjuste by a pin 49 projected through reg stering openings 50 in the walls of the body portion and a selected one of the spaced apart openings 51 through the arm 43.. The body portion 46 has it's wallcdntiguous to the cylinder 6- curved toconform with-the latter and to thereby prevent lateral movement of the andbeing liquid-tight, can be readily transported from place to of an automobile.

"I claim: v

- 1.v In a device of the character described,

a working cylinder closed at one end and provided with an inlet and outlet at its closed end, a ram slidable in the cylinder and protruding from, the open end of the latter, said ram being arranged at its inner end to "engage the" cylinder-,with a liquidtight fit, means forintrodhcing a liquid into the cylinder through the inlet, means for controlling the. passage of the fluid through the outlet, whereby the ram will be. moved along the cylinder away fromlthe closed end when the outlet is closed, a-by-pass conduit place, as in the tool box for conducting liquid from the cylinder i when the ram has been moved a certain dis tance, said ram being formed with a-longitudinally extending groove in its outer wall extending from a point spaced from its ininder, and means for guiding the ram in its 'ner end to the end protruding from the cyl-.

. movement in the'cylinder to occasion the communication of the groove with the bypass conduit. v

2. In a hydraulic jack of the oharacter 5 described,--a liquid holding receptacle, a cylinder, a ram slidably mounted in said cylinder, aby-pass communicating at one end with said, cylinder and at its lower end with;

said receptacle, said ram being fashioned with a longitudinally extending groove on its side wall and means for guidlng said ram in said cylinder, whereby the groove in said ram may be in registration with said by-pass when said ram is retracted in said cylinder,

ARTHUR PAOLI. 

